The nipple in MR mammography: Normal and pathologic findings

Purpose: To differentiate between patterns of contrast enhancement in normal and pathologic nipples. Materials and Methods: The examinations were performed on a 1.0 T imager, using a dynamic FLASH-3D-Sequence (9/3/50 ). The enhancement of nipples and normal breast parenchyma was evaluated retrospectively in 156 patients. In total, 277 nipples and the parenchyma of 101 patients could be evaluated. In 5 cases histologically confirmed pathologies were found. Results: The 272 normal nipples were characterized by a slow and continuous increase of enhancement from 80% in the first minute to 300% in minute 10. The mean values of the normal parenchyma ranged from 20% in the first minute to 90% in minute 10. The five pathologic nipples showed a high initial signal increase reaching a maximum in the third minute (mean 400%) followed by a plateau. The enhancement of the normal nipples was of finelinear morphology in the corium, while it was nodular for the pathologic nipples. Conclusion: Normal nipples show a slowly increasing fine-linear enhancement, higher than the enhancement of normal parenchyma. Nodular enhancement with a plateau or wash-out should be considered suspicious and a further work-up is necessary. (orig.)